Optical probe

Abstract

An optical probe that is easy to manufacture and that can capture a tomographic image with high resolution has a proximal end to be connected to an OCT device and a distal end from which observation light exits, and includes an optical fiber, a light collection optical system and a light deflection optical system that are optically connected to the optical fiber at the distal end, a sheath that accommodates the optical fiber, the light collection optical system, and the light deflection optical system, and that causes the observation light deflected to exit through the curved surface portion laterally, and a compensation portion that is accommodated in the sheath, that extends in a first direction over a range including a part of the optical fiber and the Grin lens, and that compensates an optical aberration that occurs when the observation light passes through the curved surface portion.

1 . An optical probe having a proximal end configured to be connected to a measurement unit of an OCT device and a distal end configured to exit observation light, comprising:
 an optical fiber configured to transmit the observation light between the proximal end and the distal end;   a light collection optical system that is optically connected to the optical fiber at the distal end and that is configured to collect the observation light that exits from the optical fiber;   a light deflection optical system that is optically connected to the light collection optical system at the distal end and that is configured to deflect the observation light that exits from the optical fiber;   a sheath that extends in a first direction, that accommodates the optical fiber, the light collection optical system, and the light deflection optical system in the first direction, that includes a curved surface portion having a curvature in a section perpendicular to the first direction, and that in configured to cause the observation light deflected by the light deflection optical system to pass through the curved surface portion in a second direction intersecting the first direction such that the observation light exits from the distal end; and   a compensation portion that is accommodated in the sheath, that extends in the first direction over a range including a part of the optical fiber, the light collection optical system, and the light deflection optical system, and that is configured to compensate an optical aberration that arises from penetration of the observation light through the curved surface portion.   
     
     
         2 . The optical probe according to  claim 1 ,
 wherein the compensation portion covers an outer circumference of the light deflection optical system, the light collection optical system, and the part of the optical fiber and is integrally formed with the light deflection optical system, the light collection optical system, and the optical fiber.   
     
     
         3 . The optical probe according to  claim 2 ,
 wherein the optical fiber includes, in the sheath, a coating and a glass fiber exposed in a manner in which the coating is removed, and   wherein the compensation portion covers the outer circumference of the light deflection optical system, the light collection optical system, and the glass fiber and is integrally formed with the light deflection optical system, the light collection optical system, and the optical fiber.   
     
     
         4 . The optical probe according to  claim 3 ,
 wherein the light collection optical system is a Grin lens having a diameter that is larger than a diameter of the glass fiber and that is less than a diameter of the coating, and   wherein an outer diameter of the compensation portion around the outer circumference of the glass fiber is equal to the outer diameter of the compensation portion around the outer circumference of the light collection optical system.   
     
     
         5 . The optical probe according to  claim 3 ,
 wherein an outer edge of the compensation portion is located inside an outer edge of the coating in a view of the optical fiber, the light collection optical system, and the light deflection optical system that are integrally formed, the view being from a light deflection optical system side in the first direction.   
     
     
         6 . The optical probe according to  claim 1 ,
 wherein a refractive index of the compensation portion is larger than a refractive index of a medium filled between the compensation portion and the sheath, and   wherein a curvature of a part of the compensation portion through which the observation light passes is less than a curvature of a part of the compensation portion other than the part through which the observation light passes.   
     
     
         7 . The optical probe according to  claim 6 ,
 wherein the compensation portion includes a first molded part that extends in the first direction and that includes the part through which the observation light passes, and a second molded part that extends in the first direction, that faces the part through which the observation light passes, and that does not include the part through which the observation light passes,   wherein the first molded part and the second molded part are adjacent to each other across an interface that corresponds to a largest section of the compensation portion, that is perpendicular to a plane extending in the first direction and the second direction, and that is parallel to the first direction, and   wherein a center of the optical fiber is located on a second molded part side from the interface in the section perpendicular to the first direction.   
     
     
         8 . The optical probe according to  claim 7 ,
 wherein the optical probe has a step on an outer surface of an interface portion between the first molded part and the second molded part.   
     
     
         9 . The optical probe according to  claim 1 ,
 wherein the compensation portion includes, on a part extending in the first direction, a protrusion that protrudes from an outer circumference of the compensation portion toward the sheath.   
     
     
         10 . A method for manufacturing the optical probe according to  claim 1 , comprising:
 defining a space in combination with a first mold for forming a first molded part of the compensation portion that extends in the first direction and that includes a part through which the observation light passes and a second mold for forming a second molded part of the compensation portion that is adjacent to and faces the first molded part and that does not include the part through which the observation light passes;   disposing the part of the optical fiber, the light collection optical system, and the light deflection optical system inside the space; and   filling the inside of the space with a resin and curing the resin.   
     
     
         11 . The method according to  claim 10  for manufacturing the optical probe,
 wherein the first mold and the second mold are separated from each other such that a center of the optical fiber is located on a second molded part side from an interface between the first molded part and the second molded part in the section perpendicular to the first direction.